A founding member of the nine-nation international coalition that designed the F-35 stealth fighter, Canada once planned to acquire 65 of the stealth fighter jets for its air force. Under this scenario, the F-35's builder, Lockheed Martin (NYSE:LMT), stands to enjoy a potential $30 billion payday for first selling Canada the airplanes, and then servicing and maintaining them for decades thereafter.

That's one scenario, at least. Under another, Canada may buy no F-35s, and Lockheed may get no money at all -- unless Boeing (NYSE:BA) accidentally saves the day.

F/A-18 Super Hornet.

Don't look now, but Boeing F/A-18 fighter jet sales could be shifting into reverse. Image source: Boeing.

Canadian second thoughts

Late last year, in a development disturbing for Lockheed, the Royal Canadian Air Force announced plans to acquire 18 new fighter jets to replace its aging fleet of 60 "CF-18" Canadian variant F/A-18A fighters. Canada's new planes won't be fifth-generation Lockheed Martin F-35s, though. Rather, the Canadian government has opted to purchase 18 Boeing-built fourth-generation F/A-18 fighters as a stopgap measure, while it continues to debate the merits of Lockheed's F-35.

This could turn out to be a pricey proposition for Canada. By delaying a decision on Lockheed's F-35, the Canadian government has indicated it will have to pay to "modernize" its existing CF-18 aircraft, plus pay for the new Boeing F/A-18s. Even so, Canada may ultimately end up having to buy additional new fighters anyway, because eventually, those old CF-18s will become too obsolete to fly, even with upgrades.

As the country continues to hem and haw, Lockheed is forced to cool its heels and await a final decision on whether one of the F-35s founding developers will ever buy the plane for itself at all. Canada's National Post now reports it's entirely possible Canada won't finish upgrading its air force until "the late 2020s."

Will Boeing save Lockheed Martin's Canadian bacon?

Here's where this story gets really interesting. Last month, Boeing -- the beneficiary of Canadian contrariness to date -- petitioned the Trump Administration U.S. International Trade Commission to punish Canadian aerospace champion Bombardier (NASDAQOTH:BDRBF) for offering its new CSeries civilian aircraft to U.S. airlines for sale at unfairly low prices.

Last year, as you may recall, Delta Air Lines (NYSE:DAL) placed a 75-plane order (upgradable to 125 planes) for Bombardier's CS100 civilian airliner. List-priced at $69.5 million per plane, the CS100 already costs less than the cheapest Boeing 737 (the 737-700), which lists at $82.4 million. But media reports suggest that Bombardier may have offered to sell Delta its CS100s for as much as 70% off of list price -- as little as $21 million per plane. Additional deals to sell CSeries jets to United Airlines, Spirit, and JetBlue are also said to be in the works -- and this has Boeing feeling nervous.

In retaliation for Boeing's move, Canada is now threatening to "review" its planned purchase of the 18 F/A-18s described above. Canadian Foreign Minister Chrystia Freeland says Boeing's ITC challenge is "clearly aimed at blocking Bombardier's new aircraft" from competing against the Boeing 737, and vowed to "defend the interests of Bombardier, the Canadian aerospace industry, and our aerospace workers" -- up to and including by killing the Boeing fighter jet deal in retaliation.

Boeing's boneheaded move

This would be horrible news for Boeing -- and it's an entirely unnecessary crisis of Boeing's own making. Granted, Boeing's 737 is one of the airplane maker's bigger profit makers in Commercial Airplanes. But according to Freeland, Boeing itself has admitted that Bombardier's tiny CS100 doesn't really compete with most larger Boeing 737s. (CSeries actually poses more of a threat to small passenger jets from Embraer than it does to Boeing).

What's more, the profits Boeing earns on Commercial Airplanes pale in comparison to the margins it makes in Military Aircraft. According to data from S&P Global Market Intelligence, Boeing Commercial Aircraft sales yield operating margins of only about 4.8% on average. In contrast, Military Aircraft sales earn Boeing margins of better than 9.8%.

In other words, the F/A-18s that Boeing had all but succeeded in selling to the Royal Canadian Air Force are all but guaranteed to be twice as profitable for Boeing as any 737s it might succeed in selling thanks to its ITC action. And any additional F/A-18s Boeing might succeed in selling to Canada, should the latter elect not to buy F-35s from Lockheed, would likewise be twice as profitable for Boeing.

Now, Boeing has put all of those profits at risk. And it has no one to blame but itself.

Rich Smith has no position in any stocks mentioned. The Motley Fool recommends Embraer-Empresa Brasileira. The Motley Fool has a disclosure policy.